Technical Field
The present invention relates to a target recognition apparatus.
Related Art
Pre-crash safety (referred to, hereinafter, as “PCS” (registered trademark)) is known that enables a vehicle to perform operations when an object (such as a preceding vehicle, an oncoming vehicle, a guardrail, a manhole cover and other iron plates, or a pedestrian) ahead of the vehicle is detected using a millimeter-wave radar or the like and the probability of a collision between the detected object and the vehicle is determined to be high. The operations that are performed are, for example, an operation to avoid collision (such as a warning or automatic braking) and an operation to reduce impact caused by a collision (such as automatic braking or automatic seatbelt retraction).
PCS control requires the capability to reliably operate its control in response to an object with which the probability of collision is high. At the same time, PCS control requires the capability to suppress the operation of unnecessary control in response to an object with which the probability of collision is low. In this way, PCS control is required to actualize both of the two contradictory capabilities at a high level. Therefore, accurate identification of the type of object ahead is required.
JP-A-2007-132748 describes a technique in which a detected object is presumed to be an automobile when the reception strength of reflection waves in the millimeter-wave radar is relatively high. The detected object is presumed to be a pedestrian when the reception strength is relatively low.
In the technique in which the type of object is presumed based on the reception strength of reflection waves in the millimeter-wave radar, as described above, a problem occurs in that erroneous estimation (classification) of the type of object may occur depending on the cruising state of the vehicle.
For example, a guardrail is set along a curve. A manhole is set on a road surface near the guardrail in the vicinity of the curve exit. In this situation, from the perspective of the vehicle, the manhole and a portion of the guardrail may overlap in the vicinity of the curve entrance. In this case, based on the reflection waves from the manhole and the reflection waves from the portion of the guardrail, the manhole and the portion of the guardrail may be erroneously presumed to be a single object with which the probability of collision is high.
When an erroneous estimation of the type of object such as this occurs, unnecessary control is performed immediately before the vehicle passes over the manhole. For example, automatic braking or automatic seatbelt retraction is performed. Therefore, the above-described conventional technique has room for improvement in terms of improving the capabilities of PCS control.
The above-described issue is not limited to PCS control. Rather, the issue is a common issue among vehicle control in which an object that meets predetermined conditions is detected from ahead of the vehicle and the vehicle is made to perform a predetermined operation related to the detected object. Such vehicle control includes, in addition to PCS, adaptive cruise control (referred to, hereinafter, as “ACC”), lane keep assist (referred to, hereinafter, as “LKA”), lane departure warning (referred to, hereinafter, as “LDW”), and the like.